Improved expanding mandrel



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Leners Patent No. 76,372, ma apra 7,1868.

IMPROVED EXPANDING MANDREL.

fitte .stimuli maar in im tigen Eutin rztin mit mating part it tigefaire.

TO ALL WHOM IT MAY CONGERN:

Be it known that I, DAVID L. ALLEN, of Williamsport, in the county ofLycoming, and State of Pennsyivania,`have invented al new and improvedExpanding Chuck for Turning-Pulleys; and I de hercby declare that thefollowing is a full, clear, and exact description of the constructionand operation of the saine, reference being had to the accompanyingdrawings, and to the letters of reference marked thereon.

The nature of my invention consists', first, in the combination andarrangement of a chuck with the arbors and cones thereof, whereby thepulley or other work to be turned may be held rigidly thereon by thesections ofthe said chuck being expanded to fit the hole of the pulley;second, the combination and arrangement of annular plates,setscrews, andsprings, with the chuck, whereby the sections thereof may be united anddrawn together around the arbors and cones by the said springs, andtheir expansion suitably governed by the screws attached at either endof the sections, through slots in the said plates. y

Tovenable any one skilled in the art to make and use my invention, Iwill proceed to describe its construction and operation.

A and B are the small arbors of themandrel; A A" and B B are the cones.The vchuck is composed of five sections, (see Nos. 1, 2, 3, 4, and 5, atletter G, which represents an end View of the sections united together,forming the chuck.) A longitudinal view of one of the sections is also7shown by the letter E, which view represents the form of itsconstruction internally. In the view immediately above, several of thesections are removed from the arbors and cones, in order to show clearlythe relative position of the chuck to the cones,

which, as will be seen, on beingr forced therein by rotating 'the arborsA and B, will necessarily expand the sections, which may be expanded ateither end of the chuck, to suit the inclined or tapering shape of thehole of the pulley, or both ends at once, to conform them to a straighthole. In either caso, the pressure exerted by the arbors will spread thesections so as to fit the hole of the pulley tightly, and thus render itimmovable; -and it will be obvious that the sections may lbe expanded toiit the holes of pulleys of different diameters.

'.lhe arbor A has a key-seahdesigned for the reception of a' key to keepthe small arbor from turning when in use.

` The sections are held and drawn together by springs, D, which areplaced in circular grooves at each end of the chuck, and attachedthereto by screws (see Nos'. I, 2, 3, 4, and 5, at letter G) passedthrough quadrilaterallyshaped slots, P, in annular plates C, which areplaced over the springs on the ends of the chuck, the expansion of eachsection thereof being controlled by its screw in the slot of the plate.

Having thus fully described my invention, 'what I claim therein as new,and desire to` secu-re by Letters Patent, is

'lhe combination and arrangement of thel chuck, annular plates C,set-screws and springs D, connectingscrcw It, with the arbors'A and B,and cones A A and B B, substantially in the manner and for the purposes'as herein set forth.

DAVID L. ALLEN.

Witnesses:

lI?. C. CAMPBELL. VC. K. Gnmnns.

